This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
醘 combines 酉 (wine vessel) with 盍, which likely contributes the sound. The exact historical development is uncertain.
The left side 酉 suggests a wine jar, and the right side 盍 looks like a lid over a dish. Picture a covered wine vessel, but remember its meaning is unclear.
For コウ, imagine a wine jar with a lid that makes a hollow 'koh' sound when tapped: koh -> コウ.